.presentations.wrap {
    max-width: 1100px;
    margin: 6rem auto;
    padding: 0 1.5rem;
}

.presentations .lead {
    margin: 0.6rem 0 0;
    color: var(--secondary);
}

.presentations .grid {
    margin-top: 1.8rem;
    display: grid;
    gap: 1.6rem;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.presentations .slide .viewer {
    position: relative;
    display: grid;
    place-items: center;
    width: 100%;
    aspect-ratio: 16 / 9;
    border-radius: 12px;
    overflow: hidden;
    background: #0f0f0f;
}

.presentations .thumb,
.presentations .pdf-frame {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    display: block;
    border: 0;
}

.presentations .pdf-canvas {
    display: block;
    max-width: 100%;
    max-height: 100%;
    z-index: 1;
}

.presentations .thumb {
    object-fit: cover;
    opacity: 0.95;
    transition: opacity 0.3s ease, transform 0.35s ease;
}

.presentations .viewer:hover .thumb {
    opacity: 1;
    transform: scale(1.01);
}

.presentations .thumb-fallback {
    display: grid;
    place-items: center;
    color: #e6e6e6;
    letter-spacing: 0.08em;
    font-size: 0.82rem;
    background: linear-gradient(135deg, #1a1a1a, #2c2c2c);
}

.presentations .badge-year {
    position: absolute;
    left: 0.6rem;
    top: 0.6rem;
    background: rgba(0, 0, 0, 0.45);
    color: #eee;
    font-size: 0.8rem;
    padding: 0.2rem 0.4rem;
    border-radius: 0.4rem;
    z-index: 2;
}

.presentations .badge-tags {
    position: absolute;
    right: 0.6rem;
    top: 0.6rem;
    display: flex;
    gap: 0.3rem;
    flex-wrap: wrap;
    z-index: 2;
}

.presentations .badge-tags .tag {
    background: rgba(0, 0, 0, 0.45);
    color: #ddd;
    font-size: 0.75rem;
    padding: 0.2rem 0.4rem;
    border-radius: 0.4rem;
}

.presentations .slide-nav {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    z-index: 3;
    border: 0;
    border-radius: 0.6rem;
    padding: 0.42rem 0.6rem;
    background: rgba(0, 0, 0, 0.45);
    color: #eee;
    cursor: pointer;
    opacity: 0;
    transition: opacity 0.25s ease;
}

.presentations .slide-nav.prev {
    left: 0.6rem;
}

.presentations .slide-nav.next {
    right: 0.6rem;
}

.presentations .viewer:hover .slide-nav,
.presentations .viewer:focus-within .slide-nav {
    opacity: 1;
}

.presentations .meta {
    margin-top: 0.75rem;
}

.presentations .summary {
    margin: 0 0 0.55rem;
    color: var(--secondary);
    font-size: 0.92rem;
}

.presentations .actions {
    display: flex;
    align-items: center;
    gap: 0.8rem;
    flex-wrap: wrap;
}

.presentations .actions a {
    font-size: 0.88rem;
    text-decoration: none;
}

.presentations .actions a:hover {
    text-decoration: underline;
}

.presentations .page-indicator {
    font-size: 0.84rem;
    color: var(--secondary);
}

@media (hover: none) {
    .presentations .slide-nav {
        opacity: 1;
    }
}

@media (max-width: 700px) {
    .presentations.wrap {
        margin-top: 5rem;
        padding: 0 1rem;
    }
}